As the use of mobile communications devices, such as cellular telephones, becomes more pervasive, there will be more wireless networks that support the wireless communication of such devices. Furthermore, the more such devices are used in different facets of users' lives, such as personal use and work use, the usage becomes fragmented. For example, a single user may have one device for personal use, and a second device for work use, where the devices utilize different wireless communications network technologies.
Some mobile communications devices include multiple subscriber capabilities. That is, such a mobile device can have more than one subscriber identification module (SIM) for subscribing to, and providing service on, different carrier networks. The single mobile device, with multiple SIMs, can provide the user access to multiple wireless communications networks. Continuing the example above, the single user would be able to use one device for work and personal communications, both with different subscriber identifications.
One such device for accessing multiple networks as different subscribers, is the dual-SIM dual-standby (DSDS) mobile device with carrier aggregation (CA) (hereinafter DSDS+CA mobile device). The different SIMs provide subscriptions/access to different wireless communications networks, such as LTE, SRLTE, WCDMA, GSM, etc. The dual-standby capabilities of the mobile device choose which SIM is active to send/receive a call, and cause the other SIM to go out of service. Carrier aggregation, however, enables the device to coordinate data received from the different wireless communications networks. Thus, when a DSDS+CA mobile device receives a call, on either subscriber technology, the other subscriber technology goes out of services. As an example, when such a device utilizes a first subscription to an SRLTE/CSFB wireless communications network and a second subscription to an SRLTE/3G/2G wireless communications network, a non-voice over LTE call on either subscription/SIM will cause the LTE capabilities of the mobile device to go out of service.
When global navigation satellite system (GNSS) positioning is initiated in a DSDS+CA mobile device during a non-LTE voice call, the mobile device will connect to a communications network. The time to first fix for the GNSS positioning purposes may take a considerable amount of time, thereby consuming processing and power resources of the mobile device, based on the device's ability to receive GPS signals and the associated strength of those GPS signals. This problem is exacerbated when the DSDS+CA mobile device is indoors, or any other low visibility environment, which can reduce or prevent the DSDS+CA mobile device's ability to obtain the necessary GPS signals. Furthermore, when the positioning process is initiated in response to an emergency voice call, the length of time and lack of precision for obtaining the mobile device's position, can be unacceptable in an emergency location scenario.